<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <style>
    * {
      box-sizing: border-box;
    }

    body {
      background-color: #eafbff;
      background-image: linear-gradient(
        to bottom,
        #eafbff 0%,
        #eafbff 50%,
        #5290f9 50%,
        #5290f9 100%
      );
      font-family: "Muli", sans-serif;
      display: flex;
      align-items: center;
      justify-content: center;
      height: 100vh;
      margin: 0;
    }

    nav {
      background-color: #fff;
      padding: 20px;
      width: 80px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 3px;
      box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
      transition: width 0.3s linear;
      overflow-x: hidden;
    }

    nav.active {
      width: 350px;
    }

    nav ul {
      display: flex;
      list-style-type: none;
      padding: 0;
      margin: 0;
      width: 0;
      transition: width 0.3s linear;
    }

    nav.active ul {
      width: 100%;
    }

    nav ul li {
      transform: rotateY(0deg);
      opacity: 0;
      transition: transform 0.3s linear, opacity 0.3s linear;
    }

    nav.active ul li {
      opacity: 1;
      transform: rotateY(360deg);
    }

    nav ul a {
      position: relative;
      color: #000;
      text-decoration: none;
      margin: 0 10px;
    }

    .icon {
      background-color: #fff;
      border: 0;
      cursor: pointer;
      padding: 0;
      position: relative;
      height: 30px;
      width: 30px;
    }

    .icon:focus {
      outline: 0;
    }

    .icon .line {
      background-color: #5290f9;
      height: 2px;
      width: 20px;
      position: absolute;
      top: 10px;
      left: 5px;
      transition: transform 0.3s linear;
    }

    .icon .line2 {
      top: auto;
      bottom: 10px;
    }

    nav.active .icon .line1 {
      transform: rotate(-765deg) translateY(5.5px);
    }

    nav.active .icon .line2 {
      transform: rotate(765deg) translateY(-5.5px);
    }
  </style>
  <body>
    <nav id="nav" class="active">
      <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">Works</a></li>
        <li><a href="#">About</a></li>
        <li><a href="#">Whatever</a></li>
      </ul>
      <button class="icon" id="toggle">
        <div class="line line1"></div>
        <div class="line line2"></div>
      </button>
    </nav>
    <script>
      const nav = document.getElementById("nav");
      const toggle = document.getElementById("toggle");
      toggle.addEventListener("click", () => {
        nav.classList.toggle("active");
      });
    </script>
  </body>
</html>
